Date:

Wednesday, September 21, 2016, 4:00pm

Location:

Haller Hall (Room 102), Geological Museum, 24 Oxford Street

Abstract:

This talk will discuss the results presented in our recent paper (Science 351, p.1414 and online aad6253). Recent work to analyze the minimal cell, and plans for further analysis will also be discussed. We used whole-genome design and complete chemical synthesis to minimize the 1079-kilobase pair synthetic genome of Mycoplasma mycoides JCVI-sym.o. An initial design, based on collective knowledge of molecular biology combined with limited transposon mutagenesis data, failed to produce a viable cell. Improved transposon mutagenesis methods revealed a class of quasi essential genes that are needed for robust growth, explaining the failure of our initial design. Three cycles of design, synthesis, and testing, with retention of quasi-essential genes, produced JCVI-syn3.o (s31 kilobase pairs, 473 genes), which has a genome smaller than that of any autonomously replicating cell found in nature. JCVI-syn3.o retains almost all genes involved in the synthesis and processing of macromolecules. Unexpectedly, it also contains 149 genes with unknown biological functions. JCVl-syn3.o is a versatile platform for investigating the core functions of life and for exploring whole-genome design. Our goal is a minimal cell for which we know the function of every gene. Computer modeling of such a cell can test our understanding of life at a molecular level.